1. Field of the Invention
The invention relates to a process for protecting a load receiving plane such as, in particular, the platform of a handling pallet, as well as to a device for implementing the process. It will quite especially find an application with the manufacturers of automatic handling equipment, such as automated palletizing installations.
2. The Prior Art
In numerous industries, manufactured products are generally packed on pallets. This facilitates the handling operations as pallets can be manipulated conveniently with the help of fork lift trucks. Under these circumstances, lorries can be loaded and unloaded very quickly and the products can be stored in store rooms fitted with racks in which the loaded pallets are stowed.
There exist different formats of pallets used to suit as well as possible the dimensions and goods to be placed thereon. In practice, the dimensions range from formats of 800 mm.times.800 mm to 1,600 mm.times.1,600 mm.
Automatic palletizing installations are also known. Their role is to ensure the loading of the goods onto pallets via a processing line. For this purpose, the installations include a linear conveyor to supply empty pallets, and are supplied with the packages to be loaded onto the pallets.
By means of a system for gripping the packages, known to a man of the art, such as, for example, a vacuum sucker or other means, the packages are manipulated from a supply track to the platform of the pallet to be loaded. Once loading is completed, the pallet is directed by the linear conveyor to a store or a loading area. These installations make it possible to operate continuously and at fast rates.
However, certain more or less fragile goods cannot be loaded directly onto the platform of the pallet. The latter is, in fact, made up of nailed wooden boards having a rough appearance.
In addition, there can be nailing defects, in which case nail points are present on the surface. As a result, in certain applications, it is essential to cover the load receiving plane, and particularly the platforms of the pallets, with a protective screen, before depositing a load thereon. This protective screen is generally known in French as a `macule`, or protective sheet, and currently takes the form of a sheet of corrugated cardboard more or less adapted to the dimensions of the pallet by the warehouseman.
In automatic palletizing installations, the protective sheet is installed in a work station located upstream of the loading area. This operation is performed manually as, in addition to installation properly speaking on the platform of the pallet, it is also necessary to dimension the protective sheet.
Indeed, many automatic palletizing installations have cause to work on different pallet formats depending on the loads to be placed thereon. Under these conditions, an appropriate protective sheet has to be put in place on each pallet format. An operator is thus responsible for installing protection corresponding to the format of the pallets.
Not only is this operation costly as regards labour but it is also necessary to have different protective sheet formats available to meet different requirements. This being the case, a major shortcoming is encountered in automated palletizing installations capable of operating with different pallet formats in which the platforms have to be protected by a protective sheet.